Improving speech quality of CELP coder
J.I. Lee, C.K. Un · Electronics Letters · 1989
Although the speech quality of the code excited linear prediction (CELP) coder at 4800bit/s is relatively good, it is still perceived as rough or noisy. In the letter we propose a residual shaping method that produces, without signal distortion, quality comparable to that obtained by adaptive postfiltering. The proposed method is particularly effective in the multiple tandeming environment.